Beverly Hills billionaires Stewart and Lynda Resnick made headlines in 2019 — and not just for their agribusiness empire.

The Resnicks, who ranked No. 7 on the Business Journal’s Wealthiest Angelenos list, turned heads in September with a $750 million donation to Caltech for research into sustainability practices and combatting climate change.

The university plans to build the 75,000-square-foot Resnick Sustainability Resource Center at a projected cost of $100 million.

It’s the second-largest single donation to a U.S. university — exceeded only by former New York Mayor Michael Bloomberg’s $1.8 billion donation to his alma mater, Johns Hopkins University, announced in November 2018.

Stewart Resnick said donations of this magnitude are necessary to achieve what he termed “breakthrough innovations” that can “manage the climate crisis.”

Climate change has already had an impact on the Resnicks’ agricultural empire, with the long drought earlier this decade decreasing crop yields and crimping water supplies.

The Resnicks’ West Los Angeles-based Wonderful Co. also made news in 2019, announcing in June that it would launch its first new product in several years —seedless lemons. While seedless lemons have been around for decades, they have remained a niche category with limited growth in recent years. Wonderful Co. is gambling it can change that.

The company obtained exclusive rights to a variety of seedless lemon developed by an unidentified party, then spent years adapting it and growing it in California. In November, Wonderful launched a marketing campaign to convince consumers to buy the product.

Wonderful’s goal is to do for seedless lemons what it did for pomegranates a decade earlier: turn an underappreciated fruit into a cash gusher. Wonderful reported $4.6 billion in revenue last year, landing it at No. 4 on the Business Journal’s Largest Private Companies list.

Keep Reading: 2019 Year in Review Special Report